The European Union and Britain are stuck in a "disturbing deadlock” in their Brexit negotiations over the EU divorce bill, the EU’s chief Brexit negotiator Michel Barnier says.

Barnier made the comments at a press conference on Thursday at the end of a fifth round of Brexit talks with the UK’s Brexit Secretary David Davis at the European Commission headquarters in Brussels.

"We are at a deadlock on this question which is extremely disturbing," Barnier said. “Constructive talks had clarified some points but there had not been any great steps forward on central issues.”

The European Council will decide next week whether sufficient progress has been made on Brexit talks to begin trade discussions, as the UK wants.

Only if EU leaders approve there has been "sufficient progress" on these three issues would negotiators be allowed to move towards the more complex issue of future trade ties between the EU and Britain.

EU officials have been complaining that the British side has been weaseling out of its obligations and failing to address the three key points raised in previous Brexit talks: EU citizen rights, Northern Ireland's border and a divorce bill.

Barnier said there has not been enough progress to move to the next stage of Brexit talks.

"I am not currently able to recommend to next week's European Council to open discussions on the future relationship," he said.

UK Prime Minister Theresa May delivered a speech in Florence, Italy, last month to encourage EU leaders to agree that “sufficient progress” has been made on the withdrawal for discussions to turn to trade.

At Thursday’s press conference, Davis said he still hoped for the go-ahead for trade talks when EU leaders meet next week.

"I hope the member states will recognize the progress we've made and take a step forward in the spirit of the prime minister's Florence speech," Davis said, adding that it was "in the interests of Europe and the UK."

EU President Donald Tusk warned Tuesday that the bloc might rethink whether a Brexit deal is possible if there is no progress by the end of the year.

Tusk also ruled out the possibility of moving onto the trade talks phase at the October 19 summit, though he said he hoped to be able to by the next summit in December.